<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ page contentType="image/jpeg" import="java.awt.*, java.awt.image.*,java.util.*,javax.imageio.*,java.io.OutputStream" %> 
<%
	String path = request.getContextPath();
	String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>


<%! 
Color getRandColor(int fc,int bc) { 
	Random random = new Random(); 
	if(fc>255) fc=255; 
	if(bc>255) bc=255; 
	int r=fc+random.nextInt(bc-fc); 
	int g=fc+random.nextInt(bc-fc); 
	int b=fc+random.nextInt(bc-fc); 
	return new Color(r,g,b); 
} 
%> 

<% 
	out.clear();//这句针对resin服务器，如果是tomacat可以不要这句 
	out = pageContext.pushBody(); 
	response.setHeader("Pragma","No-cache"); 
	response.setHeader("Cache-Control","no-cache"); 
	response.setDateHeader("Expires", 0); 
	int width=60, height=20; 
	BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); 
	Graphics g = image.getGraphics(); 
	Random random = new Random(); 
	g.setColor(getRandColor(200,250)); 
	g.fillRect(0, 0, width, height); 
	g.setFont(new Font("Times New Roman",Font.PLAIN,18)); 
	g.setColor(getRandColor(160,200)); 
	for (int i=0;i<155;i++) { 
		int x = random.nextInt(width); 
		int y = random.nextInt(height); 
		int xl = random.nextInt(12); 
		int yl = random.nextInt(12); 
		g.drawLine(x,y,x+xl,y+yl); 
	} 
	String sRand=""; 
	for (int i=0;i<4;i++){ 
		String rand=String.valueOf(random.nextInt(10)); 
		sRand+=rand; 
		g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110))); 
		g.drawString(rand,13*i+6,16); 
	} 
	
	// 将认证码存入SESSION 
	session.setAttribute("codeImage",sRand); 
	g.dispose(); 
	OutputStream output=response.getOutputStream(); 
	ImageIO.write(image, "JPEG", output); 
	output.flush();
	output.close(); 
%>
